Simulation of passage of a laser radiation through dispersing media in view of a frequency shift

The version of a Monte-Carlo method for simulation of passage of a laser radiation through dispersing media based on use of an integrated evaluation algorithm is described. The algorithm allows one to take into account multi-layer medium, reflection and refraction of light on the boundaries between layers, and also frequency shift at light scattering. The results for skin tissues and polystyrene solution are submitted. The given algorithm is used for modeling processes taking place at two-photon photodynamic therapy.